The present invention relates to an apparatus for suppressing torque variations in an internal combustion engine and more particularly to a power generation control method and apparatus for an internal combustion engine well suited for reducing torque variations caused by combustion pressure variations during the idle operation of an internal combustion of a vehicle as well as vibrations and noise induced by such torque variations.
In the past, it has been well known in the art that in an engine the variation of a cylinder pressure due to the intake and compression of a mixture and the expansion of combustion gas is not uniform with degrees of crankshaft rotation thus causing a torque variation. The torque variation results in vibrations which in turn cause deterioration in the riding comfortability of the vehicle. With a view to overcoming this deficiency, as disclosed for example in JP-A-61-61930, JP-A-58-185938 JP-A-55-1431 and JP-A-62-255534, methods have been proposed in which a counter torque is developed in the crankshaft of an engine in synchronism with an increase in the varying torque of rotation caused in the engine, thereby suppressing the variations in the torque of rotation.
In accordance with these known techniques, it is necessary to perform a series of processing steps of detecting a varying torque changing at a high speed, computing the amount of load torque required for cancelling the varying torque and applying the load torque, and no consideration is given to the time delay required for the computational operation. Also, while a generator is used as a means of cancelling the varying torque in the method of JP-A-58-185938, to produce the required torque for cancelling the varying torque of an engine necessitates the installation of a generator having an excessive capacity thus giving rise to a problem from the economy point of view. There is another problem of increasing the engine load torque and decreasing the rotational speed.